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INFO: rcu detected stall in sys_epoll_wait

Status: closed as invalid on 2019/12/04 14:14
Subsystems: mm cgroups
[Documentation on labels]
First crash: 1883d, last: 1881d
▶ ▼ Similar bugs (6)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in sys_epoll_wait (6) ext4 3 206d 221d 0/28 auto-obsoleted due to no activity on 2024/10/03 13:07
upstream INFO: rcu detected stall in sys_epoll_wait (2) kernel 15 1846d 1847d 0/28 closed as invalid on 2020/01/08 05:23
upstream INFO: rcu detected stall in sys_epoll_wait (7) fs 3 93d 101d 0/28 auto-obsoleted due to no activity on 2025/01/24 21:05
upstream INFO: rcu detected stall in sys_epoll_wait (3) kernel 1 1846d 1846d 0/28 closed as invalid on 2020/01/08 05:33
upstream INFO: rcu detected stall in sys_epoll_wait (4) kernel 21 1846d 1846d 0/28 closed as invalid on 2020/01/09 08:13
upstream INFO: rcu detected stall in sys_epoll_wait (5) input fs usb syz error 2 827d 1345d 0/28 closed as dup on 2021/05/25 09:57

Sample crash report:
rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	1-...!: (10499 ticks this GP) idle=5e2/1/0x4000000000000002 softirq=12283/12283 fqs=6 
	(t=10501 jiffies g=6209 q=332)
rcu: rcu_preempt kthread starved for 10490 jiffies! g6209 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
rcu: RCU grace-period kthread stack dump:
rcu_preempt     R  running task    29104    10      2 0x80004000
Call Trace:
 context_switch kernel/sched/core.c:3385 [inline]
 __schedule+0x9a0/0xcc0 kernel/sched/core.c:4081
 schedule+0x181/0x210 kernel/sched/core.c:4155
 schedule_timeout+0x14f/0x240 kernel/time/timer.c:1895
 rcu_gp_fqs_loop kernel/rcu/tree.c:1661 [inline]
 rcu_gp_kthread+0xed8/0x1770 kernel/rcu/tree.c:1821
 kthread+0x332/0x350 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
NMI backtrace for cpu 1
CPU: 1 PID: 8107 Comm: udevd Not tainted 5.4.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1fb/0x318 lib/dump_stack.c:118
 nmi_cpu_backtrace+0xaf/0x1a0 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x174/0x290 lib/nmi_backtrace.c:62
 arch_trigger_cpumask_backtrace+0x10/0x20 arch/x86/kernel/apic/hw_nmi.c:38
 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline]
 rcu_dump_cpu_stacks+0x15a/0x220 kernel/rcu/tree_stall.h:254
 print_cpu_stall kernel/rcu/tree_stall.h:455 [inline]
 check_cpu_stall kernel/rcu/tree_stall.h:529 [inline]
 rcu_pending kernel/rcu/tree.c:2827 [inline]
 rcu_sched_clock_irq+0xe25/0x1ad0 kernel/rcu/tree.c:2271
 update_process_times+0x12d/0x180 kernel/time/timer.c:1726
 tick_sched_handle kernel/time/tick-sched.c:167 [inline]
 tick_sched_timer+0x263/0x420 kernel/time/tick-sched.c:1310
 __run_hrtimer kernel/time/hrtimer.c:1517 [inline]
 __hrtimer_run_queues+0x403/0x840 kernel/time/hrtimer.c:1579
 hrtimer_interrupt+0x38c/0xda0 kernel/time/hrtimer.c:1641
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1110 [inline]
 smp_apic_timer_interrupt+0x109/0x280 arch/x86/kernel/apic/apic.c:1135
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829
 </IRQ>
RIP: 0010:__memcg_kmem_uncharge+0x42/0x1a0 mm/memcontrol.c:2911
Code: 00 00 fc ff df 4c 8d 77 38 4d 89 f5 49 c1 ed 03 41 80 7c 05 00 00 74 08 4c 89 f7 e8 78 fe fa ff 4d 8b 3e b8 01 00 00 00 89 d9 <d3> e0 4d 85 ff 0f 84 de 00 00 00 4c 39 3d a4 f0 8c 07 0f 84 2c 01
RSP: 0018:ffffc90001b27ad0 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffea00025b9780
RBP: ffffc90001b27b00 R08: 000000000003a728 R09: ffffed10128a1a8f
R10: ffffed10128a1a8f R11: 0000000000000000 R12: ffffea00025b9780
R13: 1ffffd40004b72f7 R14: ffffea00025b97b8 R15: 0000000000000000
 memcg_kmem_uncharge include/linux/memcontrol.h:1402 [inline]
 free_thread_stack+0x12e/0x590 kernel/fork.c:284
 release_task_stack kernel/fork.c:440 [inline]
 put_task_stack+0xa3/0x130 kernel/fork.c:451
 finish_task_switch+0x3f1/0x550 kernel/sched/core.c:3256
 context_switch kernel/sched/core.c:3388 [inline]
 __schedule+0x9a8/0xcc0 kernel/sched/core.c:4081
 schedule+0x181/0x210 kernel/sched/core.c:4155
 schedule_hrtimeout_range_clock+0x3c7/0x510 kernel/time/hrtimer.c:2130
 schedule_hrtimeout_range+0x2a/0x40 kernel/time/hrtimer.c:2175
 ep_poll+0xa4d/0xe80 fs/eventpoll.c:1915
 do_epoll_wait+0x1ee/0x260 fs/eventpoll.c:2294
 __do_sys_epoll_wait fs/eventpoll.c:2304 [inline]
 __se_sys_epoll_wait fs/eventpoll.c:2301 [inline]
 __x64_sys_epoll_wait+0x9a/0xb0 fs/eventpoll.c:2301
 do_syscall_64+0xf7/0x1c0 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7ff664d25943
Code: 00 31 d2 48 29 c2 64 89 11 48 83 c8 ff eb ea 90 90 90 90 90 90 90 90 83 3d b5 dc 2a 00 00 75 13 49 89 ca b8 e8 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 34 c3 48 83 ec 08 e8 3b c4 00 00 48 89 04 24
RSP: 002b:00007ffda1508b38 EFLAGS: 00000246 ORIG_RAX: 00000000000000e8
RAX: ffffffffffffffda RBX: 000000000132c250 RCX: 00007ff664d25943
RDX: 0000000000000004 RSI: 00007ffda1508c00 RDI: 0000000000000007
RBP: 0000000000625500 R08: 00007ffda1508b20 R09: 00007ffda15440b8
R10: 000000000000ee42 R11: 0000000000000246 R12: 0000000001345530
R13: 00007ffda1509c57 R14: 0000000000000005 R15: 000000000132c250

Crashes (148):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/12/04 13:16 upstream 63de37476ebd 0ecb9746 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/04 11:34 upstream 63de37476ebd 0ecb9746 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/04 11:27 upstream 63de37476ebd 0ecb9746 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/04 10:23 upstream 63de37476ebd 0ecb9746 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/04 09:18 upstream 63de37476ebd 0ecb9746 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/04 08:08 upstream 63de37476ebd 0ecb9746 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/04 07:04 upstream 76bb8b05960c ae13a849 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/04 06:55 upstream 76bb8b05960c ae13a849 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/04 05:55 upstream 76bb8b05960c ae13a849 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/04 04:49 upstream 76bb8b05960c ae13a849 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/04 03:28 upstream 76bb8b05960c ae13a849 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/04 02:22 upstream 76bb8b05960c ae13a849 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/04 00:52 upstream 76bb8b05960c ae13a849 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/04 00:32 upstream 76bb8b05960c ae13a849 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 23:23 upstream 76bb8b05960c ae13a849 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 21:40 upstream 76bb8b05960c ae13a849 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 20:36 upstream 76bb8b05960c ae13a849 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 20:36 upstream 76bb8b05960c ae13a849 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 19:16 upstream 76bb8b05960c ae13a849 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 18:04 upstream 76bb8b05960c ae13a849 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 16:06 upstream 76bb8b05960c ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 15:01 upstream 76bb8b05960c ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 13:41 upstream 76bb8b05960c ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 13:31 upstream 76bb8b05960c ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 12:06 upstream 76bb8b05960c ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 11:00 upstream 596cf45cbf6e ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 09:53 upstream 596cf45cbf6e ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 08:50 upstream 596cf45cbf6e ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 07:22 upstream 596cf45cbf6e ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 07:17 upstream 596cf45cbf6e ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 07:05 upstream 596cf45cbf6e ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 06:01 upstream 596cf45cbf6e ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 05:37 upstream 596cf45cbf6e ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 05:15 upstream 596cf45cbf6e ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 05:06 upstream 596cf45cbf6e ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 05:06 upstream 596cf45cbf6e ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 04:48 upstream 596cf45cbf6e ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 04:41 upstream 596cf45cbf6e ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 04:20 upstream 596cf45cbf6e ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 03:47 upstream 596cf45cbf6e ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 03:41 upstream 596cf45cbf6e ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 03:21 upstream 596cf45cbf6e ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/02 21:20 upstream 596cf45cbf6e ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
* Struck through repros no longer work on HEAD.